Although compositions containing polycarbonate and impact modifiers based on EPDM rubber (e.g. AES) or acrylate rubber (ASA) are stable to ageing as compared with corresponding PC/ABS compositions, they generally have inadequate low-temperature strength. Compositions containing polycarbonate and impact modifiers based on silicone rubbers or silicone-rich silicone-acrylate composite rubbers are stable to ageing as compared with corresponding PC/ABS compositions and generally also have good low-temperature strength, but mouldings produced therefrom are distinguished by a high-gloss surface appearance. In order to avoid lacquering the components after injection moulding, components produced from such compositions are often required to have a low-gloss surface.
DE-OS 2 037 419 discloses moulding compositions containing polycarbonate and rubber-like acrylate polymers (for example a graft polymer of acrylonitrile and styrene on acrylate rubber, referred to as ASA hereinbelow) which have improved resistance to the formation of hairline cracks and to weathering as compared with corresponding polycarbonate/ABS compositions.
U.S. Pat. No. 4,550,138 discloses moulding compositions containing from 60 to 97 wt. % polycarbonate and from 3 to 40 wt. % AES graft copolymer having a rubber content of from 30 to 80 wt. %, which are distinguished as compared with pure polycarbonate in that they have improved strength while their dimensional stability under heat is not substantially impaired.
EP-A 0 369 201 discloses compositions containing polycarbonate, a graft copolymer based on polysiloxane, and a graft copolymer based on diene rubber (for example ABS).
WO-A 98/008900 discloses moulding compositions containing aromatic polycarbonate, a graft polymer based on alkyl acrylates, styrenes and unsaturated nitrites, a copolymer based on styrenes and unsaturated nitrites, a siloxane network rubber (based on silicone/acrylate), a copolymer of at least two different esters of acrylic acid or methacrylic acid, and optionally further components. The moulding compositions are strong at low temperatures and flow readily, no mention being made of the gloss of the resulting moulding compositions.